Seat belt winding method, seat belt retractor, and seat belt apparatus

Abstract

To provide a seat belt winding method, a seat belt retractor, and a seat belt apparatus capable of stopping the motor even when the seat belt is being wound and restarting the winding of the seat belt, and capable of reducing excess repetition of stopping and starting of the motor. A seat belt winding method comprises a start signal detecting step (S 1 ) for detecting a buckle release signal, a starting step (S 2 ) for actuating a motor based on a buckle release signal, an overload detecting step (S 3 ) for detecting overload on the motor, a stopping step (S 4 ) for stopping the motor when overload is detected, a waiting step (S 5 ) for stopping the motor for a certain period of time, a storage checking step (S 6 ) for checking the completion of the winding of the seat belt after a lapse of the certain period of time, and a restart determining step (S 7 ) for counting up the number of times the motor is restarted and terminating the winding operation of the seat belt (S 8 ) when the number of times the motor is restarted reaches a predetermined value.

1. A seat belt winding method for a seat belt apparatus having a motor for winding up a seat belt, the method comprising:
 a start signal detecting step of detecting a start signal for actuating said motor; 
 a starting step of actuating said motor according to the start signal; 
 an overload detecting step of detecting the occurrence of an overload on said motor in operation; 
 a stopping step of stopping said motor when overload is detected; 
 a waiting step of keeping said motor in the stopped state for a certain period of time; 
 a storage checking step of checking whether or not the winding of said seat belt is completed after a lapse of said certain period of time; and 
 a restart determining step of proceeding to said starting step when the winding of the seat belt is not completed and counting up number of times said motor is restarted to terminate the winding operation of said seat belt when the number of times said motor is restarted reaches a predetermined value. 
 
     
     
       2. A seat belt winding method as claimed in  claim 1 , wherein said storage checking step terminates the winding operation of said seat belt without carrying out said restart determining step when the winding of said seat belt is completed. 
     
     
       3. A seat belt winding method as claimed in  claim 1 , further comprising a wait cancelling step of proceeding to said starting step when a wait cancelling signal is detected during said waiting step. 
     
     
       4. A seat belt winding method as claimed in  claim 1 , further comprising a restart cancelling step of terminating the winding operation of said seat belt when a seat belt wearing signal is detected during said waiting step. 
     
     
       5. A seat belt winding method as claimed in  claim 1 , further comprising a previous storage checking step of checking whether or not the winding of said seat belt is completed just after said start signal detecting step and proceeding to said starting step when the winding of said seat belt is not completed. 
     
     
       6. A seat belt winding method as claimed in  claim 1 , wherein said start signal is a signal for detecting the wearing state of said seat belt or the opening state of a vehicle door. 
     
     
       7. A seat belt retractor having a spool for winding up a seat belt; and a motor for rotating said spool, and comprising:
 an overload detecting means for detecting the occurrence of an overload on said motor; 
 a storage checking means for checking whether or not the winding of said seat belt is completed; and 
 a motor control means for controlling the operation of said motor, wherein 
 said motor control means actuates said motor when a start signal for actuating said motor is received, stops said motor when overload is detected by said overload detecting means and keeps said motor in the stopped state for a certain period of time, restarts said motor according to a signal from said storage checking means when the winding of said seat belt is not completed after a lapse of the certain period of time, and terminates the winding operation of said seat belt when the number of times said motor is restarted reaches a predetermined value. 
 
     
     
       8. A seat belt retractor as claimed in  claim 7 , wherein said motor control means terminates the winding operation of said seat belt without restarting said motor according to a signal from said storage checking means when the winding of said seat belt is completed. 
     
     
       9. A seat belt retractor as claimed in  claim 7 , wherein said motor control means restarts said motor rather than waiting a lapse of the certain period of time when receiving a wait cancelling signal. 
     
     
       10. A seat belt retractor as claimed in  claim 7 , wherein said motor control means terminates the winding operation of said seat belt rather than waiting a lapse of said certain period of time when receiving a seat belt wearing signal. 
     
     
       11. A seat belt retractor as claimed in  claim 7 , wherein said motor control means checks by said storage checking means whether or not the winding of said seat belt is completed after receiving a start signal for starting said motor, and starts said motor when the winding of said seat belt is not completed. 
     
     
       12. A seat belt retractor as claimed in  claim 7 , wherein said start signal is a signal for detecting the wearing state of said seat belt or the opening state of a vehicle door. 
     
     
       13. A seat belt apparatus comprising: a seat belt for restraining an occupant, a seat belt retractor for winding up said seat belt in such a manner as to allow said seat belt to be withdrawn, a tongue which is slidably supported by said seat belt, and a buckle which is fixed to a vehicle structural object and can be latched with said tongue, wherein
 said seat belt retractor has a spool on which the seat belt is wound, and a motor for rotating said spool, and comprises: 
 an overload detecting means for detecting the occurrence of an overload on said motor, a storage checking means for checking whether or not the winding of said seat belt is completed, and a motor control means for controlling the operation of said motor, wherein 
 said motor control means actuates said motor when receiving a start signal for actuating said motor, stops said motor when overload is detected by said overload detecting means, keeps said motor in the stopped state for a certain period of time, restarts said motor according to a signal from said storage checking means when the winding of said seat belt is not completed after a lapse of the certain period of time, and terminates the winding operation of said seat belt when the number of times said motor is restarted reaches a predetermined value. 
 
     
     
       14. A seat belt apparatus as claimed in  claim 13 , wherein said motor control means terminates the winding operation of said seat belt without restarting said motor according to a signal from said storage checking means when the winding of said seat belt is completed. 
     
     
       15. A seat belt apparatus as claimed in  claim 13 , wherein said motor control means restarts said motor rather than waiting a lapse of the certain period of time when receiving a wait cancelling signal. 
     
     
       16. A seat belt apparatus as claimed in  claim 13 , wherein said motor control means terminates the winding operation of said seat belt rather than waiting a lapse of said certain period of time when receiving a seat belt wearing signal. 
     
     
       17. A seat belt apparatus as claimed in  claim 13 , wherein said motor control means checks by said storage checking means whether or not the winding of said seat belt is completed after receiving a start signal for starting said motor, and starts said motor when the winding of said seat belt is not completed. 
     
     
       18. A seat belt apparatus as claimed in  claim 13 , wherein said start signal is a signal for detecting the wearing state of said seat belt or the opening state of a vehicle door.